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If you increase the temperature in a reversible reaction, what happens? |
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The endothermic reaction will increase. |
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If you decrease the temperature in a reversible reaction, what happens? |
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The exothermic reaction will increase. |
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If you increase the pressure in a reversible reaction, what happens? |
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The high pressure will favour the reaction which produces less volume. |
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If you decrease the pressure in a reversible reaction, what happens? |
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The low pressure will favour the reaction which produces more volume. |
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What is the concentration used in the Haber Process? |
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200 Atmospheres. |
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What is the temperature used in the Haber Process? |
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450°C. |
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What is an exothermic reaction? |
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A reaction which gives out heat. |
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What is an endothermic reaction? |
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A reaction which takes in heat. |
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In an endothermic reaction, how does the temperature change? |
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The temperature decreases. |
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In an exothermic reaction, how does the temperature change? |
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The temperature increases. |
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Explain what is meant by the term isotope. |
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Isotopes are different atomic forms of the same element, which have the same number of protons but a different number of neutrons. |
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What types of elements bond ionically? |
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Non-metals and metals. |
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Why do ionic structures have high melting and boiling points? |
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Because they have very strong chemical bonds between all the ions in the giant structure. |
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Why do ionic structures conduct electricity when they are in solution? |
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Because when dissolved, the ions are separate and can carry the charge. |
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Why do ionic structures conduct electricity when they are molten? |
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Because the ions are free and they can carry the charge. |
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What type of elements bond covalently? |
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Non-metals. |
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Why are the melting and boiling points of simple molecular substances very low? |
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Because there are very weak intermolecular forces between the molecules, so they do not require much energy in order to be broken. |
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What state are molecular substances in at room temperature? |
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Gases or liquids. |
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Why don't molecular substances conduct electricity? |
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Because there are no ions. |
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Describe the structure and bonding of Diamond. |
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Each carbon atom forms 4 covalent bonds in a very rigid giant covalent structure. |
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Describe the structure and bonding of Graphite. |
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Each carbon atom only forms 3 covalent bonds, creating layers which are free to slide over each other. The layers are held together loosely so Graphite is soft and slippery. |
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Why does Graphite conduct electricity? |
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There are de-localised electrons which can carry the charge. |
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